This invention relates to data recording and in particular to novel improved multi-disk arrangements of data records and to associated means for automatically partitioning them.
Workers in the art of generating and using flexible recording disks are aware of its various advantages and shortcomings. As mentioned in the cited U.S. Ser. No. 711,647, magnetic disks have well known advantages, and in the form of "flexible disks" can serve as a "unit record" medium that is compact, light, and is readily transported, stored, and handled, interchangeably with other like disks. Flexible (or "floppy") disks are now widely used in the data processing arts.
Workers recognize that costs may be reduced in many cases by replacing a rigid magnetic recording disk with a "floppy" disk. Floppy disks can be fashioned from well-known polyester sheet material (e.g., the familiar polyethylene terephthalate used for magnetic tape) with a magnetic coating thereon--this plastic being simply cut into the shape of a circular disk with a central mounting hole to accommodate the familiar drive-spindle. Packs of such "prior art" floppy disks are well known to workers; e.g., as shown in FIG. 1; with a conventional disk therefrom illustrated in FIG. 2.
The present invention is directed toward improving the design of such "floppy packs" and of associated spacer means such that automatic pneumatic partition means may be employed to split the pack and expose any selected disk surface. That is, an improved inter-disk spacer for a "floppy disk pack" according to the invention is particularly adapted for such automatic partitioning--using surprisingly simple means and methods as described hereinafter.
Prior efforts with flexible disks:
Workers are familiar with prior approaches to the design and manufacture of floppy disks and to related equipment for handling them. Several are described in U.S. Pat. No. 4,086,640.
Workers are aware that for many applications of floppy disk pack applications, it is of paramount importance to minimize disk cost while yet maintaining accurate, reliable operation. Thus, it is often desirable to fabricate all floppy disks in a pack by a single common pressing operation, with all disks identical--yet still render the disks uniquely "selectable" when collected into a pack. The invention teaches this, and other techniques, using simple partitioning expedients. For example, with the invention a relatively conventional disk pack may be pneumatically partitioned with jet-select means disposed permanently on the associated drive and without locating, or manipulating, mechanical elements within the pack itself.
The present invention is directed toward providing improved multi-disk record units (disk packs) which are better adapted to meet the foregoing problems and objectives in a manner satisfying minimum-cost objectives. The invention maintains the convenience of packaging a number of floppy disks in an "end-wise" partitionable file, while prescribing improved simplified techniques for partitioning with mechanical select elements outside the pack. This file may take the form of a few floppy disks bound together in portable pack or many "floppies" permanently affixed upon a hollow spindle (either being pneumatically partitioned from within the stack's hub).
As mentioned, the function of partitioning with jet-select means has been proposed heretofore in several, rather probablematical techniques involving the mechanical elements injected into the confines of a floppy disk pack--something which is best avoided for many reasons (e.g., to maintain simplicity of pack construction and interchangability between packs, etc.). One such technique (described in some of the cited applications) involves a perforation of the floppy disks themselves and the intrusion of mechanical "select-fingers" into the confines of the pack. Various disadvantages inhere in such a technique, such as the requirement for completely arresting pack rotation--something ill-advised if one wishes to minimize "access time".
A related jet-select technique (also mentioned in some of the cited applications) locates a distributor piston within the pack-hub and affords "jet-select" by positioning a port opposite a selected inter-disk spacer. The subject invention avoids the problems associated with injecting mechanical means into the confines of the disk pack and operates to switch partition jets between disk spacers with means disposed completely outside the confines of the pack--thereby providing pneumatic, "end-wise" partitioning of the pack.
Workers will appreciate many advantages inhering in this approach to pneumatic partitioning--one being that it uses relatively simple conventional machine elements and can accommodate a relatively conventional flexible pack structure--except, of course, that inter-disk spacers must be apertured in a prescribed pattern and cut-out radially.
Most importantly, the invention allows for pneumatic partitioning of a floppy pack without stopping the hub--or even slowing it down--and avoids the associated loss of time and energy, etc. The invention also partitions without need for placing a piston within the pack-hub and without any of the related axial-positioning means (such an axially translatable piston being disclosed in the cited applications). Such intra-hub pistons complicate pack structure (e.g., either each pack must be made to include such a piston, or else the related drive must be fitted with such a piston and the pack adapted to be coupled to it). And such intra-hub pistons are inherently tricky to position; for instance, the jet orifice must be very precisely located so as to distinguish between two adjacent spacers (separated by a few mils or less), yet without leaking significant jet-air through the adjacent spacer. Also, it is typically problematical to efficiently couple such jet ports to a selected spacer.
The substitution of jet select/distributor means outside the pack instead is advantageous in several respects. It can be combined with an array of apertured spacers for the "end-wise" transmission of the partitioning jet streams and direction thereof to the appropriate inter-disk gap. Thus, it brings many obvious advantages, including the ability to relocate mechanical jet-distribution means outside of the crowded conditions and intricate spacing problems). For instance, such an external distributor arrangement allows a designer to amplify the translation distance between spacers virtually at will (i.e., make select-translation as widely spaced as is convenient, such as indicated below with respect to the embodiments of FIGS. 5, 9 or 10). And, in special cases it allows a designer to implement gap-selection without any translation or positioning of mechanical parts--a stunning step-forward in the art (e.g., see FIG. 10 embodiment below).
The present invention is directed towards providing improved flexible disk packs with associated apertured spacer means--means which are better adapted to meet the foregoing problems and objectives.
The foregoing and other features, objects and advantages according to the present invention will be more fully appreciated and become more apparent upon consideration of the following description of preferred embodiments taken in conjunction with the attached drawings, wherein like reference indicia denote like elements.